It's not much more than a battery and a bunch of wires. In fact, you could actually make it yourself.

But that doesn't mean that you should try it at home. Though no one so far has reported seizures or other negative effects, sending any amount of electricity into your brain without the supervision of a medical professional is not the best idea. That all said, it's shockingly easy to build a transcranial direct current stimulator, or tDCS, just like the one used in all of those experiments.

Folks have been talkingabout the mind-hacking benefits of low-level electrical brain stimulation for years, and scientists even say we should have access to it. Why hasn't anyone developed a product one could buy so we don't have to McGyver our own? Scientific American's blog today discusses the ethics of a so-called "electrical thinking cap." Would it be fair? Would parents be weirdly manipulating their kids' brains? Would it be like electronic brain doping?

Maybe the explanation is simpler. Maybe no one sees a profit in something that any middle-school science student could build for 10 bucks? Sure, you could maybe buy the one the Harvard researchers used, but it's really intended for clinics and costs close to $1,000. So where's the consumer version?

I can imagine folks paying for something that's beautifully designed, painless (which apparently it is for the most part, minus some discomfort getting the thing to adhere to your head, depending on how much hair you have), and makes you smarter. Better yet, it sounds like a great app! Can one of you Y combinator kids get on that please? [Scientific American]

Update: Sgt. Michael Conte, who served in Iraq for the U.S. Army, emailed me to let me know he uses Alpha Stim cranial electrotherapy stimulator, which costs around $600 and requires a prescription, to treat symptoms of a minor brain injury suffered in 2007 following an IED explosion. "During the LONG process of my treatment and some of my comrades' treatment we have been given nuero stimulation and nuero feedback. One of the devices we are authorized to buy and use is the Alpha-stim. For some people it increases mood, for others it's a pep like caffeine, for some it calms them down enough to sleep, for me it clears the fog which I consistently live in due to my injury. The results last most of the day for me and allow me to continue my job with little loss of function," Conte told me. Thank you, sergeant, for sharing your story and for your service!